Composite slab structure



C. F. DAVIS ET AL COMPOSITE SLAB STRUCTURE 4 Sheets-Sheet 1 Filed July 28, 1930 ...||........|||...........rl.11:25:11: IIII IIII n1 A118- 8, 1933. c. F. DAVIS AL )1,921,285

COMPOS ITE SLAB STRUCTURE Filed July 28, 1950 Sheets-Sheet 2 Allg- 8, 1933. c. F. DAVIS Er AL 1,921,235

COMPOSITE SLAB STRUCTURE Filed July 28, 1930 4'Sheets-Sheet 5 glu/vantato 2..... y j kai/@54145 Aug. s, 1933@ c. F. DAvls ET AL COMPOSITE SLAB STRUCTURE 4 shears-sheet 4 Filed July 28, 1930 Patented Aug. 8, 1933- UNITED `STATES COMPOSITE SLAB STRUCTURE (.Jlai'ke F. Davis and John G. Brush, Westeld, N. J., assignors to Structural Gypsum Corporation, Linden, N. J., a Corporation of Delaappucsuon July z8. 1930. serai No. 471,137

zscmixmz.v (C1. 10s-1o) 'Ihe present invention relates to assembled byilding umts, each of which comprises a com- /posite article of manufacture made from structural elements and precast slabs of plastic material, and to a building construction embodyingthesame.

In the building art it is common practice to contruct a roof from purlins, girders, main roof supports or the like, and to erect therein precast slabs of gypsum so as to provide a substantially continuousroof surface. Where such purlins, girders, or other main roof supports are not so spaced as to conveniently take such slabs, it is common practice to provide sub-purlins, rails, or tees between the same and spaced at such a distance that slabs of any convenient length may be supported thereby. Obviously, the spacing of the sub-purlins. rails or tees may ble such as to take any convenient length of s ab.

Experience has shown that precast slabs of gypsum. either wither without metal reinforcements or fillers. and either hollow or solid, can be manufactured at a minimum cost and at maximum speed and efciency on some kind of automatic machinery of which that shown in the patent Vto Ruby, #1,692,420. is a. type, rather than individually by hand as heretofore.

Where slabs having projecting metal reinforcements are used in aroof deck construction, it becomes necessary and desirable to twist together the reinforcement ends of adjacent slab ends so as to form a ,substantially continuous with the roof slab constructions above described and they are, therefore, expensive both from the I truss element. While this operation is comparatively simple in itself, yet it involves considerable expense in that circumstances demand that skilled labor of a certain type perform this act, while unskilled labor may erect the slabs themselves. Thus. two types of labor, with the necessary foremen, supervisors, etc. are required assembied budding unit composed of two spaced apart parallel metal structuralelements holding therebetween a plurality of precast slabs of gypsum or the like, and tie rods extending be- 'tween the structural elements so that the whole may be handled as a. unit. Such a composite slab may be incorporated in a building construction such as a roof deck, by laying continuous and contiguous rows thereof, the ends of the' structural elements thereof resting on purlins. As an alternative method of erection, such composite units may be laid in rows spaced apart a distance equal to the length of the slabs incorporated in them, and then loose precast slabs erected between the rows of compomte umts, the ends of the loose slabs resting on a flange of the structural elements of. the units. In either of the above erection procedures,the same type of Vunskilled labor may beremployed to cast and assemble the slabs and units, all of which`efl'ects a material saving.

The invention further contemplates the provision of means such as a butt plate welded or .75 otherwise secured to the structural elements of a *composite slab in order to prevent theloose slabs erected according to the alternative pro- .for other purposes. f

I'he invention further comtemplates means such as a bottom plate welded or otherwise secured to the bottom of the structural elements l of a composite slab or unit, said plate having av toe or nger projecting downwardly therefrom, the plate increasing the bearing surface of the units and the toe or nger being adapted to engage the upper flange of a purlin to prevent slippage of -the units or rows of units insteep pitched roofs.

'I'he invention further consists in the novel arrangement, combination and construction of parts more fully hereinafter described and shown in the accompanying drawings.

In the drawings:- v Y' Fig. l is a partial .plan view of a roof deck erected according to this invention. 100

Fig. 2 is a sectional view of Fig. 1 along line 2-2.

Fig. 3 is an end view of Fig. 1, looking in the direction of the arrow.

Fig. 4 is a perspective view showing one method of erecting slabs according to this invention.

Fig. 5 is a perspective view of another system of erection. .l

Fig. 6 is aperspective view of a completed section of a roof.

I the Fig. 'l is a partial end view of a building construction embodying this invention.

Fig. 8 is a`partial plan view of the roof deck of Fig. 7.

Fig. 9 is a composite fragmentary view of one end of a structural element carrying a bottom plate.

Fig. 10 is a. side. view of a construction using the bottom plate of Fig. 9, and

Fig. 11 is a perspective view of a structural element to which a butt plate is attached.

Referring now to that embodiment illustrated in Figs. l, 2 and 3, there is shown a building unit composed of a plurality of lprecast slabs, one of which is shown at 1 to consistof a body of plastic material such as gypsum or the like, crystallized or set with the requisite amount of water and with or without a filler such as wood chips or the like, all of which is well-known in the art.4 This slab may preferably be made on a machine of the automatic type, of which that shown in the 'patent to Ruby #1,692,420 is illustrative, and as shown, contains core holes 2 and reinforcing rods .3 embedded in the lower Vtension zone of the slab, both the core holes and the reinforcing rods being formed and placed respectively during manufacture. It is desirable to form the slab with side flanges, shown at 4, along its longitudinal edges, which, when a) plurality of slabs` are assembled together, spaces the main bodies thereof apart and forms with the neighboring slab a channel of groove, for purposes to be ,more fully described hereinafter.

The series of slabs 1 are designed to be held together as a unitary article of manufacture, by means of spaced aparteparallel metal structural elements of any desired configuration, each of which are shown in Fig. 3 to consist of shaped sheet metal sections 5 having an upper flange 6 and two lower anges 7 and 8,-the last two flanges extending on each side of the web thereof, and forming between anges 6 and 7 a channel, adaptedrto -receive the lateral ends of the individual slabs 1. If desired, the upper portion of the slabs may be rabbetted to receive theI ange 6 so that the upper surfaces of the slab and ange may be substantially flush. The pluralityof slabs are secured between the'structural elements by means of tie rods v9-` extending from one element 5 to the other, each rod having a head 10 at one end and tightening nu 11 on the other. The tie rods 9 may be located at any convenient place in the assembled unit, and in Fig. 2 they are shown as passing beyond the side of the slab as in the case of the left-hand-rod, between the slabs as in the case of the middle rod, and

through a core hole in the slab as is the case of the right-hand rod. The length of the composite slab or building unit will determine the most expeditious number.Y and location of the. rods.

Where the rods pass between slabs, they -may be thoroughly protected from weather and re by the use of soft grouting filled into the grooves between the slabs. The end rods are likewise protected and embedded by grouting poured be-V tween the unit ends after erection. f

Obviously the structural elements may be of any desired length, depending yupon v-the distancebetween centers of the purlins upon which they rest. In some instances vit will be found that for certain lengths ofA structural elements it will be necessary to longitudinally split a slab in order to fit thesame thereto. Such a split y slabs.

l1 to consist of a butt plate 15 welded or other to punch out the toe or nger 19 from the bottom spaced apart a distance equal to the length of Upon placing the units,A

an individual slab. loose slabs 14 of the same type may then be erected between the units, the slab ends resting on the flanges 8 of the neighboring units, as lshown in Fig. 3., Such a system makes use of but one type of precast slab, both for the assembled units andl for intermediate loose rows of slabs.

Where such a system of loose and assembled slabs are used on a steep pitchedroof deck, it may be found desirable to provide means to pre- Vent accidental displacement of the loose rows of Such means lare shown in Figs. 7, 8 and wise secured to one end of each of the structural elements in the unit nearest the eaves, the structural element 16 in these figures being a solid rolled member. The corner of a loose slab abuts this plate, which eiectively prevents slippage or accidental displacement. It is to be noted that the outside tie rod 9 (left-hand end of Fig.- 2) prevents any tendency of the assembled slabs to move. Where desired, the butt plate 15 may be provided with an elongated slot 17, which serves to accommodate means such as a bolt or the like for securing a nailing strip thereto, to which a gutter or the like may be fastened. Obviously, where desirable, the bottom flange of a structural element may be slit back from the end parallel with the web thereof and that portion turned up at right angle to the flange, to serve theA same purpose as the butt plate. l

Figs. '1, 9 and 10 illustrate means in a steep pitched roof deck to prevent slippage of each assembled unit or an entire row thereof. Such means comprise a bottom plate 18 welded or otherwise secured to the bottom of the one end of the structural elements 16 of a unit, in an off- 'set manner, that is, so as to project beyond the end of the element to which it is attached. The

plate 18 is provided with a punched-out toe or flnger 19 which is adapted to engage the upper movement. is often desirable.

The plate .18 being offset from one end of the element 16, provides an increased bearing surface for the adjacent end of the neighboring element as shown in Fig. 9, which is sometimes desirable, particularly where the purlins constitute channels as at 13 (Fig. 7) and the top ange thereof is not as wide as in the case of the f purlins lof Fig. 2. j

- In some instances, it maybe found desirable flange of the structural element itself rather than form this part from the bottom plate. As a modifiedsystem of erecting such assembled building units, reference is made to the skeleton showing of Fig. 5. Here two structural elements are shown, one at 20 substantially similar to that shown at 5 in Fig. 3, except that the bottom thickness of metal is in substantially a single plane. Itscompanion'element is shown at 21 to consist of an ordinary channel, spaced from its neighbor by the heel 22 of the element 21. This space between elements 20 and 2l may be filled with grouting after erection. It will thus be seen that the construction'of Figs. 5 and 6 consist of contiguous rows of assembled units, each unit composed of a series of precast slabs tied together with rods 9 as before. Obviously tlie bottom plate of Figs.`9 and 10 may -be used with the above described pair of structural elements for the purpose as hereinbefore specied.

From the above,.t will be apparent that an assembled building unit has been provided, the individual slabsI of which may be manufactured `with minimum ease and cheapness. in .quantities and which thus assures a uniformity of production, such slabs being of' a type which makes them readily adapted to be assembled by cheap factory labor and incorporated in abuilding construction such as a roof deck, either as assembled unitsl or as loose slabs. This circumstance makes it possible to provide a slab of any desired dimension so that theA size of the ultimate units may be varied at will.

i It has been proven that the hereindescribed structural elements may be manufactured to give the requisite strength at a lower cost than the usual rails or Ts heretofore used and that the total cost of manufacture and erection of the slabs as heretofore used, far exceeds the system herein described. y A

Obviously, the building units of a row may be tied together by any desired means, so as to constitute in effect but a single continuous element. Such a construction has the advantage of added rigidity over one Where there is no positive connection between units. l

Such a roof deck may, of course, be covered /with any Waterproof or' weather-resisting material such as building or ro'ong paper, tar, all ot which is well known in the art.

While the invention has been described with reference to hollow precast slabs of gypsum, yet obviously the invention is not to be limited thereto as slabs of any desired design may -be used, it being a part of this invention to make a distinction between a composite slab which is poured between structural elements and one which is assembled from a plurality of precast slabs. Again, it is to be understood that'the invention is not concerned with any particular kind of structural element as this may take any form most suited to the particular circumstances.

The invention is therefore to be construed broadly and limited only by the scope of the claims.

1. A building construction comprising purlins, a series of spaced apart assembled building units supported thereon, each unit including a plurality of precast slabs tied together between structura-l elements, the structural elements resting upon the purlins, each of the structural elements having a base angeextending on each side of the web, and other precast slabs between the units, said slabs being' supported at each end uponthe base ange of a structural element of an assembled unit.

`2. A building construction comprising purlins, a series of structural elements havingv base iianges extending on each side of their webs and resting uponthe purlins, a plurality of precast slabs between the 'elements and having their ends restingon the base flanges thereof,

,tie means foreach two elements, the thus tied pairs of elements being spaced apart the length of a precast slab, and additional precast slabs between the spaced apart pairs of elements and resting on their base flanges. v10() 3. A building construction comprising purlins. y building units supported on said purlins and including structural elements, and means vprojecting from beneath a structural element and engaged with a purlin to prevent accidental displacement of the units, said means comprising a plate secured-to the bottom of the structural element and projecting beyond the endl thereof and having a toe engaging the purlin.

4. A building construction comprising purlins, a series of spaced apart assembled building units supported thereon, each unit comprising spaced apart structural elements, loose precast slabs supported between the rows of assembled units and resting upon anges of the structural elements, and means carried by the structural elements to prevent accidental displacement of the loose slabs, said means comprising a` butt plate secured to the end of the structural elements.

5. A building construction comprising purlins; a series of spaced apart assembled building units supported thereon', each unit comprising spaced apart structural elements, loose precast slabs secured to the end of the structural elements 1304 and having anv elongated slot'therein.

CLARKE F. DAVIS.

JOHN G. BRUSH. 

